Rapid 2-stage Norwood I for high-risk hypoplastic left heart syndrome and variants

Bilateral pulmonary artery banding facilitates the systemic ventricular outflow tract growth for biventricular and univentricular repair candidates of complex arch anomaly

Various surgical approaches address complex heart disease with arch anomalies. Bilateral pulmonary artery banding (bPAB) is a strategy for critically ill patients with complex arch anomalies. Some reports argued the potential effect of bPAB on the growth of the left ventricular outflow tract (LVOT) during inter-stage after bPAB. This study aimed to analyze the LVOT growth for biventricular repair candidates with arch anomaly and systemic ventricular outflow tract (SVOT) for univentricular repair candidates with arch anomaly. This retrospective study analyzed 17 patients undergoing initial bPAB followed by arch repair. The Z-scores of LVOT and SVOT were compared between pre-bPAB and pre-arch repair. Patient characteristics, transthoracic echocardiogram data, and PAB circumferences were reviewed. The diameter of the minimum LVOT for biventricular repair (BVR) candidates, the pulmonary valve (neo-aortic valve, neo-AoV) and the pulmonary trunk (the neo-ascending aorta, neo-AAo) for univentricular repair (UVR) candidates, and the degree of aortic or neo-aortic insufficiency in each candidate was statistically analyzed. 17 patients were divided into the UVR candidates (group U) with 9 patients and the BVR candidates (group B) with 8 patients. In group B, the median value of the Z-score of the minimum LVOT increased from -3.2 (range: - 4.1 ~ - 1.0) at pre-PAB to -2.8 (range: - 3.6 ~ - 0.3) at pre-arch repair with a significant difference (p = 0.012). In group U, the median value of the Z-score of the neo-AoV increased from 0.5 (range: - 1.0 ~ 1.7) at pre-bPAB to 1.2 (range: 0.2 ~ 1.9) at pre-arch repair with a significant difference (p < 0.01). The median value of the Z-score of the neo-AAo was also increased from 3.1 (range: 1.5 ~ 4.6) to 4.3 (range: 3.1 ~ 5.9) with a significant difference (p = 0.028). The growth of the LVOT for BVR candidates and SVOT for UVR candidates during the inter-stage between bPAB and arch repair was observed. These results suggest the potential advantage of bPAB in surgical strategies. Further research is needed to validate these findings and refine surgical approaches.

Mortality and Heart Transplantation After Hybrid Palliation of Hypoplastic Left Heart Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

Newborns with hypoplastic left heart syndrome (HLHS) who are considered at increased risk for death following Norwood/Sano surgery often undergo hybrid palliation (HP) as initial surgery. We aimed to compile the HP experience in HLHS and its variants and assess the rates of, and risk factors for, death and heart transplantation.

METHODS

CINAHL, CINAHL PLUS, PubMed/MEDLINE, and SCOPUS were systematically searched for HP outcome studies of death or heart transplantation in HLHS between 1998 and 2022. Pooled incidence was estimated, and potential risk factors were identified using random-effects meta-analysis and reconstructed time-to-event data from Kaplan-Meier curves.

RESULTS

Thirty-three publications were included in our review. Overall, of 1,162 patients 417 died and 57 underwent heart transplantation, resulting in a combined outcome of 40.7%, (474/1,162). There was a trend toward decreasing mortality risk across the stages of palliation. Pooled mortality between HP and comprehensive stage 2 palliation was 25%, after stage 2 up to Fontan palliation was 16%, and 6% post-Fontan. The incidence of death or heart transplantation was higher in high-risk patients-43% died and 10% received heart transplantation.

CONCLUSION

Our systematic review and meta-analysis found high rates of death or heart transplantation in HP of HLHS patients between HP and Fontan surgeries. All patients should be closely followed during the initial interstage period, which is associated with the highest hazard. Prospective studies on appropriate patient selection, indications, and / or alternatives, as well as refining HP strategies for managing newborns with HLHS are needed to improve outcomes.

Neurodevelopmental and functional outcome in hypoplastic left heart syndrome after Hybrid procedure as stage I

BACKGROUND

Patients with hypoplastic left heart syndrome (HLHS) undergoing staged palliation until Fontan procedure are at risk for impaired neurodevelopmental (ND) outcome. The Hybrid procedure with bilateral pulmonary artery banding, ductal stenting, and balloon atrioseptostomy may offer a less invasive stage I procedure compared to the Norwood stage I procedure avoiding early neonatal cardiopulmonary bypass (CPB) surgery. Despite altered fetal cerebral hemodynamics, the type of stage I procedure may be a covariate influencing ND outcome and functional outcome may also be altered due to postponing neonatal CPB surgery. Within this review, we analyzed ND outcome as well as functional outcome after Hybrid procedure as stage I procedure.

METHODS

The review analyzed original publications (OPs) published before March 15, 2022, identified by Cochrane, EMBASE, OVID, Scopus, and Web of science. An OP was included if short-to-long-term neurodevelopment outcome, brain development, somatic, and cardiac outcome in patients for HLHS and variants treated by Hybrid procedure were analyzed. In addition to database searches, we reviewed all references of the analyzed OP to obtain a comprehensive list of available studies. The author, year of publication, demographic characteristics of study population, study design (prospective or retrospective), study assessment, and main findings were summarized.

RESULTS

Twenty-one OPs were included with data of patients with ND outcome and functional cardiac outcome. Overall, there is an impaired mid-term ND outcome in patients with Hybrid procedure as stage I for HLHS. Only slight differences between stage I procedures (Hybrid vs. Norwood) in two comparing studies have been determined affecting right ventricular remodeling, short- and mid-term ND outcome, reduced brain growth until two years of age, sufficient quality of life, and altered hemodynamics influencing brain volumes and cerebral perfusion pattern.

CONCLUSIONS

Despite some minor differences regarding the mid-term follow-up in patients with HLHS comparing Hybrid vs. Norwood procedure, its impact on ND outcome seems rather low. This may be explained by the large number of covariates as well as the small study populations and the different selection criteria for patients undergoing Hybrid or Norwood procedure as stage I.

Small and borderline left ventricular outflow tract - a perplexing maladie

The left ventricular outflow tract (LVOT) comprises of the subvalvular area, the aortic valve, and the supravalvular region. Obstructive lesion of LVOT is a spectrum with varying levels and degree of obstruction with or without associated hypoplasia of the left ventricle. Decision-making in small and borderline LVOT can be challenging. Imaging modalities such as echocardiography and magnetic resonance imaging and scores based on imaging aid in the decision making in truly borderline cases. Newer treatment strategies like staged left ventricular rehabilitation and hybrid procedure have come to the fore in the past decade or so. Although these do not address small LVOT per se, they delay the decision-making to a more appropriate age. The goal of management in these cases is to achieve a biventricular repair whenever feasible. Several surgical techniques could be employed to achieve this goal. However, it is important to be cognizant of the fact that an overzealous approach to achieve a biventricular repair might be counterproductive. A univentricular palliation could be a safer alternative; especially considering the possibility of a future transplant candidacy.

Effect of Long-term Administration of Prostaglandin E1 on Morphologic Changes in Ductus Arteriosus

BACKGROUND

To improve survival of patients with hypoplastic left heart syndrome, combination therapy with bilateral pulmonary artery banding and prostaglandin E₁ (PGE₁)-mediated ductal patency was developed as an alternative for high-risk neonates in Japan. However, the effect of long-term PGE₁ administration on ductus arteriosus remains unclear. Synchrotron radiation-based X-ray phase-contrast tomography (XPCT) enables clear visualization of soft tissues at an approximate spatial resolution of 12.5 μm. We aimed to investigate morphologic changes in ductus arteriosus after long-term PGE₁ infusion using XPCT.

METHODS

Seventeen ductus arteriosus tissue samples from patients with hypoplastic left heart syndrome were obtained during the Norwood procedure. The median duration of lipo-prostaglandin E₁ (lipo-PGE₁) administration was 48 days (range, 3 to 123). Structural analysis of ductus arteriosus was performed and compared with conventional histologic analysis.

RESULTS

The XPCT was successfully applied to quantitative measurements of ductal media. Significant correlation was found between the duration of lipo-PGE₁ infusion and mass density of ductal media (R = 0.723, P = .001). The duration of lipo-PGE₁ administration was positively correlated with elastic fiber staining (R = 0.799, P < .001) and negatively correlated with smooth muscle formation (R = -0.83, P < .001). No significant increase in intimal cushion formation was found after long-term lipo-PGE₁ administration. Expression of ductus arteriosus dominant PGE₂-receptor EP4 almost disappeared in specimens when lipo-PGE₁ was administered over 3 days.

CONCLUSIONS

Disorganized elastogenesis and little intimal cushion formation after long-term lipo-PGE₁ administration suggest that ductus arteriosus remodeled to the elastic artery phenotype. Because EP4 was downregulated and ductus arteriosus exhibited elastic characteristics, the dosage of lipo-PGE₁ might be decreased after a definite administration period.

The Evolution of Therapeutic Strategies: Niche Apportionment for Hybrid Palliation

Hybrid palliation, the concept to stabilize univentricular circulation with bilateral pulmonary artery banding and maintenance of ductal patency, has significantly widened the therapeutic spectrum for patients with single-ventricle malformations or borderline hypoplasia. The concept has already been a part of early attempts to improve outcome in hypoplastic left heart syndrome but has not attracted much attention initially. Technical refinement and expertise have led to results that ultimately allowed the palliative strategy to gain traction and to be selectively adopted. By now, we have gained almost 2 decades of experience, and as much as hybrid palliation has changed our approach to single-ventricle management, new strategies and indications have been formed by this experience. We therefore review concepts and patterns of use of hybrid palliation as well as benefits and challenges of the respective pathways to highlight the current status of the hybrid procedure.

Interventional treatments and risk factors in patients born with hypoplastic left heart syndrome in England and Wales from 2000 to 2015

Objective

To describe the long-term outcomes, treatment pathways and risk factors for patients diagnosed with hypoplastic left heart syndrome (HLHS) in England and Wales.

Methods

The UK’s national audit database captures every procedure undertaken for congenital heart disease and updated life status for resident patients in England and Wales. Patients with HLHS born between 2000 and 2015 were identified using codes from the International Paediatric and Congenital Cardiac Code.

Results

There were 976 patients with HLHS. Of these, 9.6% had a prepathway intervention, 89.5% underwent a traditional pathway of staged palliation and 6.4% of infants underwent a hybrid pathway. Patients undergoing prepathway procedures or the hybrid pathway were more complex, exhibiting higher rates of prematurity and acquired comorbidity. Prepathway intervention was associated with the highest in-hospital mortality (34.0%).

44.6% of patients had an off-pathway procedure after their primary procedure, most frequently stenting or dilation of residual or recoarctation and most commonly occurring between stage 1 and stage 2.

The survival rate at 1 year and 5 years was 60.7% (95% CI 57.5 to 63.7) and 56.3% (95% CI 53.0 to 59.5), respectively. Patients with an antenatal diagnosis (multivariable HR (MHR) 1.63 (95% CI 1.12 to 2.38)), low weight (<2.5 kg) (MHR 1.49 (95% CI 1.05 to 2.11)) or the presence of an acquired comorbidity (MHR 2.04 (95% CI 1.30 to 3.19)) were less likely to survive.

Conclusion

Treatment pathways among patients with HLHS are complex and variable. It is essential that the long-term outcomes of conditions like HLHS that require serial interventions are studied to provide a fuller picture and to inform quality assurance and improvement.

Hypoplastic left heart syndrome: current perspectives

Since the first successful intervention for hypoplastic left heart syndrome (HLHS) was undertaken by Norwood in 1983, there have been many advancements in the pre-, intra-, and postoperative care of these children for a diagnosis that just 25 years ago was almost certainly a fatal one. This paper aims to describe the most recent trends and perspectives on the treatment of HLHS. In particular, we will discuss the five current options for HLHS, including Norwood stage I as the beginning to 3-stage palliation, transplant, true hybrid, hybrid-bridge-to-Norwood, and compassionate care.

Levoatriocardinal vein and partial anomalous pulmonary vein drainage in left-sided obstructive CHDs: diagnostic and surgical implications

We report two cases with levoatriocardinal vein and partial anomalous pulmonary venous drainage in left-sided obstructive lesions. This association may be difficult to recognise by echocardiography. Cardiac CT and MRI were crucial to define the diagnosis and to tailor the best therapeutic option.

Achieving Benchmark Results for Neonatal Palliation of Hypoplastic Left Heart Syndrome and Related Anomalies in an Emerging Program

BACKGROUND

Results of surgical management of hypoplastic left heart syndrome (HLHS) and related anomalies are often compared to published benchmark data which reflect the use of a variety of surgical and hybrid protocols. We report encouraging results achieved in an emerging program, despite a learning curve at all care levels. Rather than relying on a single preferred protocol, surgical management was based on matching surgical strategy to individual patient factors.

METHODS

From 2010 to 2014, a total of 47 consecutive patients with HLHS or related anomalies with ductal-dependent systemic circulation underwent initial surgical palliation, including 30 Norwood stage I, 8 hybrid stage I, and 9 salvage-to-Norwood procedures. True hybrid procedures entailed bilateral pulmonary artery banding and ductal stenting. In the salvage-to-Norwood strategy, ductal stenting was withheld in favor of continued prostaglandin infusion in anticipation of a deferred Norwood procedure. Cardiac comorbidities (obstructed pulmonary venous return, poor ventricular function, and atrioventricular valve regurgitation) and noncardiac comorbidities influenced the choice of treatment strategies and were analyzed as potential risk factors for extracorporeal membrane oxygenation (ECMO) support or in-hospital mortality.

RESULTS

Overall hospital survival was 81% (Norwood 83.3%, hybrid 88%, "salvage" 67%; P = .4942). Extracorporeal membrane oxygenation support was used for eight (17%) patients with two survivors. For cases with obstructed pulmonary venous return (n = 10, 21%), management choices favored a hybrid or salvage strategy (P = .0026). Aortic atresia (n = 22, 47%) was treated by a Norwood or salvage-to-Norwood. No cardiac, noncardiac, or genetic comorbidities were identified as independent risk factors for ECMO or discharge mortality in a multivariable analysis.

CONCLUSIONS

Our emerging program achieved outcomes that compare favorably to published benchmark data with respect to hospital survival. These results reflect rigorous interdisciplinary teamwork and a flexible approach to surgical palliation based on matching surgical strategy to patient factors. With major associated cardiac/noncardiac comorbidity and antegrade coronary flow, a true hybrid with ductal stenting was our preferred strategy. For high-risk situations such as aortic atresia with obstructed pulmonary venous return, the salvage hybrid-bridge-to-Norwood strategy may help achieve survival albeit with increased resource utilization.

Benefits of Balloon-Dilatable Bilateral Pulmonary Artery Banding in Patients With Hypoplastic Left Heart Syndrome and Other Complex Cardiac Anomalies

OBJECTIVES

The purpose of this study was to evaluate the potential of balloon-dilatable bilateral pulmonary artery banding (b-PAB) and its impact on the configuration of the pulmonary artery (PA).

BACKGROUND

We have previously used balloon-dilatable b-PAB as first-stage palliation for patients with hypoplastic left heart syndrome (HLHS) and other complex cardiac anomalies.

METHODS

Two pliable tapes were placed around each branch of the PA and tightened with 7-0 polypropylene sutures in a manner that allowed for the subsequent adjustment of PA diameters. We retrospectively examined the adjustability of PA diameters by balloon dilation and the need for surgical PA angioplasty at later stages.

RESULTS

From January 2010 to October 2013, we performed b-PAB in 8 patients, including 3 borderline cases between biventricular repair (BVR) and univentricular repair (UVR). The b-PAB procedures were performed at a median age of 6.5 days (range, 2-10 days). Balloon dilations were performed in 10 lesions in 4 patients. All of the procedures were performed safely. Two patients reached definite BVR. The remaining 6 patients underwent open palliative procedures with univentricular physiologies that resulted in 2 deaths unrelated to the initial b-PAB. In all but 1 of the patients, the PA configuration was properly maintained and did not require surgical pulmonary angioplasty.

CONCLUSIONS

Balloon-dilatable b-PAB can be performed safely and prevents PA distortion at later stages. This technique should be considered for patients with complex cardiac anomalies if uncertainty exists regarding the optimal surgical strategy (BVR or UVR) in early infancy.

Stage 1 hybrid palliation for hypoplastic left heart syndrome--assessment of contemporary patterns of use: an analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

OBJECTIVE

Hybrid palliation is an alternative to Norwood stage 1 for the initial management of hypoplastic left heart syndrome. Contemporary multicenter hybrid use and institutional/patient factors associated with hybrid use relative to the Norwood have not been evaluated. We describe hybrid use in relation to institutional volume, patient factors, and short-term outcomes.

METHODS

Infants aged 60 days or less listed in The Society of Thoracic Surgeons Congenital Heart Surgery Database (2010-2012) undergoing initial palliation of hypoplastic left heart syndrome were included. Annual institutional hybrid use rates were calculated: [hybrid procedures/(Norwood + hybrid + transplant procedures)]. In-hospital outcomes for primary hybrid and primary Norwood were compared and stratified by high (defined as ≥50%) versus low (defined as ≤10%) institutional hybrid use.

RESULTS

Of 1728 patients (100 centers), most (n = 1496, 87%) underwent an index Norwood; 232 patients (13%) underwent an index hybrid procedure. Preoperative patient risk factors were more prevalent in patients undergoing the hybrid procedure. Only 13 of 100 institutions were high hybrid users, and these tended to have lower annual hypoplastic left heart syndrome index case volume. Unadjusted in-hospital mortality was higher for the hybrid compared with the Norwood procedure (30% vs 16%; P < .001). In-hospital mortality for the hybrid procedure was not associated with hybrid use (26% among institutions with low use vs 28% among institutions with high use). However, centers with high hybrid use had higher mortality after the Norwood (43%) compared with centers with low hybrid use (16%).

CONCLUSIONS

Few centers currently select the hybrid procedure for most infants with hypoplastic left heart syndrome. Although unadjusted in-hospital hybrid mortality is higher than Norwood mortality, potential risk factors are more prevalent among hybrid cases. Institutions with higher hybrid use have lower hypoplastic left heart syndrome case volume and higher Norwood mortality.

Decision-Making for Surgery in the Management of Patients with Univentricular Heart

A series of technical refinements over the past 30 years, in combination with advances in perioperative management, have resulted in dramatic improvements in the survival of patients with univentricular heart. While the goal of single-ventricle palliation remains unchanged - normalization of the pressure and volume loads on the systemic ventricle, the strategies to achieve that goal have become more diverse. Optimal palliation relies on a thorough understanding of the changing physiology over the first years of life and the risks and consequences of each palliative strategy. This review describes how to optimize surgical decision-making in univentricular patients based on a current understanding of anatomy, physiology, and surgical palliation.

Hybrid palliation for critical systemic outflow obstruction: neither rapid stage 1 Norwood nor comprehensive stage 2 mitigate consequences of early risk factors

OBJECTIVE

Hybrid palliation with branch pulmonary artery banding (bPAB) has become increasingly common in the early management of patients with critical left ventricular outflow obstruction. Optimal subsequent surgical palliation remains undefined.

METHODS

We retrospectively reviewed patients undergoing initial bPAB for single ventricle physiology with systemic outflow obstruction (2001-2013, n = 37). Patients were stratified by subsequent surgical palliation: stage 1 Norwood (St1N, n = 14), comprehensive stage 2 (CompSt2, n = 11), and none (n = 12).

RESULTS

bPAB was performed at a median of 4 days and 2.7-kg, post-bPAB mortality was increased in patients with aortic atresia (odds ratio [OR] = 3.8, 95% confidence interval [CI] = 0.9-15.8) or birth weight <2 kg (OR = 13.8, 95% CI = 1.4-136.4). Palliation strategy did not affect transplant-free survival through second-stage palliation (St1N: 71.4%, CompSt2: 72.7%, P = .9). Among CompSt2 patients, there was a trend toward poorer survival with aortic atresia (0% vs 80%, P = .09); birth weight <2.5 kg was associated with decreased survival (0% vs 89.0%, P = .01). A trend toward lower survival with low birth weight was evident among St1N patients (<2 kg, OR = 0.1, 95% CI = 0.01-1.9, P = .09). CompSt2 mortality occurred on postoperative days 0 and 1. Mortality following St1N occurred at a median of 38.5 days (range = 23.5-104.5). Among survivors of stage 2 palliation, Fontan completion was performed in the same number of patients in each group (St1N: 6/8, 75%, CompSt2: 6/8, 75%).

CONCLUSIONS

Both St1N and CompSt2 are viable options for subsequent palliation following initial hybrid procedure. Transplant-free survival and eventual Fontan candidacy are similar between groups. Delaying surgical palliation with the CompSt2 did not mitigate the impact of early risk factors such as low birth weight and aortic atresia.